Mammalian PLD directly interacts with kinases like PKC, ERK, TYK and controls the signalling indicating that PLD is activated by these kinases.[10] As choline is very abundant in the cell, PLD activity does not significantly affect choline levels, and choline is unlikely to play any role in signalling.

It is possible that, though PA and DAG are interconvertible, separate pools of signalling and non-signalling lipids may be maintained. Studies have suggested that DAG signalling is mediated by polyunsaturated DAG while PLD derived PA is monounsaturated or saturated. Thus functional saturated/monounsaturated PA can be degraded by hydrolysing it to form non-functional saturated/monounsaturated DAG while functional polyunsaturated DAG can be degraded by converting it into non-functional polyunsaturated PA.[11][12][13]

A lysophospholipase D called autotaxin was recently identified as having an important role in cell-proliferation through its product, lysophosphatidic acid (LPA).